40 CFR 50.6 - National primary and secondary ambient air quality standards for PM 10.

§ 50.6 National primary and secondary ambient air quality standards for PM 10.

(a) The level of the national primary and secondary 24-hour ambient air quality standards for particulate matter is 150 micrograms per cubic meter (µg/m 3), 24-hour average concentration. The standards are attained when the expected number of days per calendar year with a 24-hour average concentration above 150 µg/m 3, as determined in accordance with appendix K to this part, is equal to or less than one.

(b) [Reserved]

(c) For the purpose of determining attainment of the primary and secondary standards, particulate matter shall be measured in the ambient air as PM10 (particles with an aerodynamic diameter less than or equal to a nominal 10 micrometers) by:

(1) A reference method based on appendix J and designated in accordance with part 53 of this chapter, or

(2) An equivalent method designated in accordance with part 53 of this chapter.

[ 52 FR 24663, July 1, 1987, as amended at 62 FR 38711, July 18, 1997; 65 FR 80779, Dec. 22, 2000; 71 FR 61224, Oct. 17, 2006]

This is a list of United States Code sections, Statutes at Large, Public Laws, and Presidential Documents, which provide rulemaking authority for this CFR Part.

This list is taken from the Parallel Table of Authorities and Rules provided by GPO [Government Printing Office].

It is not guaranteed to be accurate or up-to-date, though we do refresh the database weekly. More limitations on accuracy are described at the GPO site.


United States Code

Title 40 published on 2015-08-22

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 40 CFR Part 50 after this date.

  • 2017-02-15; vol. 82 # 30 - Wednesday, February 15, 2017
    1. 82 FR 10726 - Response to December 9, 2013, Clean Air Act Section 176A Petition From Connecticut, Delaware, Maryland, Massachusetts, New Hampshire, New York, Pennsylvania, Rhode Island and Vermont
      GPO FDSys XML | Text
      ENVIRONMENTAL PROTECTION AGENCY
      Notice of public hearing and extension of comment period.
      Public Hearing. The public hearing will be held on March 14, 2017, in Washington, DC. Please refer to SUPPLEMENTARY INFORMATION section for additional information on the public hearing. Comments. Comments must be received on or before April 13, 2017.
      40 CFR Parts 50 and 51